WHEN a Soviet military convoy actually, and on exact schedule, pulled out of Jalalabad on May 15 and headed back toward home, it made news for a single, specific reason. This is not the first time that the Soviets, or their czarist predecessors, have given up territory which had been taken by their armed forces and held for a time. But it is the first time since imperial Russia became the Soviet Union that Moscow has been in the process of giving up a country that had, at least in theory, become a ``socialist'' state. The ``Brezhnev Doctrine'' had declared that once a country became socialist it must forever remain socialist, and Moscow would enforce that doctrine with all of its armed might.
The 1979 invasion of Afghanistan was done under the Brezhnev Doctrine. The regime there was nominally ``socialist.'' It was threatened by Islamic fundamentalism. Moscow went in to save ``socialism.'' Of course it went in for other reasons as well.
We in the outside world can never know what reasons weighed most heavily in the 1979 decision to send a substantial Soviet military force into Afghanistan. Perhaps military reasons were uppermost. Soviet air bases in southern Afghanistan could provide cover for any military operation Moscow might at some time have in mind into Iran, Pakistan, India, or even China.
Possession of the airfields of Afghanistan gave Soviet armed forces a major extension of military ``reach'' toward the Indian Ocean. That is of course a main reason the United States objected, and responded first with a broad range of economic ``sanctions'' and later with substantial military help to the native Afghan resistance movement.
But whatever the main reason for the original Soviet invasion, the excuse, the cover, and perhaps in part a real reason was the Brezhnev Doctrine.
The degree of conversion to socialism of any substantial part of the Afghan population is open to question. It is highly doubtful that many Afghans came to believe sincerely in doctrines of Marx. But the regime that existed in Kabul in 1979 was socialist by declaration and training. It professed to practice the teachings of Marx. It at least aspired to be a Marxist ally of Moscow.
Now all that is coming to an end. There is still a slight possibility that the present ``socialist'' regime will hold out for a little while after the last Soviet soldier has gone. Beyond doubt Moscow will leave behind enough weapons for that regime to defend itself, just as Americans left ample weapons behind in Vietnam for the South Vietnamese to defend themselves.
But a regime cannot defend itself with weapons alone. There must be men willing to use those weapons.
The probability is that the soldiers of the Kabul regime will melt away in the wake of the departing Soviet Army. And then we will be watching a fascinating sequel to the Afghan story.
There is no such thing as a universal rule governing the rise and fall of empires. In the long run those survive longest which have the soundest economic base. The British Empire began as a natural association between the industrial center in England and the source of raw materials and the market for the finished goods in the colonies.
The decline of the British Empire began with the industrialization of the colonies. India no longer needs to send its cotton to Lancashire to be finished. The Indians finish their own cotton and can build their own railroad rolling stock as well. The reasons for the British Empire declined as the industrialization of the colonies progressed.
There is nothing Afghanistan needs from Moscow, or Moscow from Afghanistan (other than bases). There is more, but not much more, economic basis for the Soviet association with the countries of Eastern Europe. All would do the bulk of their trade with Western Europe, if free to do so. Now that the Brezhnev Doctrine has been breached by one, it could in theory be breached by others.
It is not to be expected that the countries of Eastern Europe will soon break away from Moscow. But the theoretical possibility that did not exist before, exists now.